Commands used in the shop?

I have one final issue about this mod. Am I able to add something from another plugin to the shop? I'm using this mod with an ATM plugin and in that plugin I can spawn debit cards. I want players to walk up to human NPCs and collect the debit cards from them. How can I achieve this? 

You set up a shop inside guishop and attach the (HumanNPC) npc to that shop inside the config and disable the global shop for that new shop so that it's only available to the npc vendor when players go up to it.  Now inside the shop, you created create custom items as commands and run the command inside guishop for that plugin assuming it has console commands.

Many people use RC plugin, Vehicles plugin, and many more inside their shops. 

Some examples of custom items. All of these work with their associated plugins

    "Furnace Splitter": {
      "DisplayName": "Furnace Splitter",
      "Shortname": "furnacesplitter",
      "EnableBuy": true,
      "EnableSell": false,
      "Image": "",
      "SellPrice": 1.0,
      "BuyPrice": 3000.0,
      "BuyCooldown": 1296000,
      "SellCooldown": 0,
      "KitName": null,
      "Command": [
        "oxide.grant user $player.id furnacesplitter.use"
      ],
      "SkinId": 0
    },
    "MiniCopter License": {
      "DisplayName": "MiniCopter License",
      "Shortname": "minicopter.license",
      "EnableBuy": true,
      "EnableSell": false,
      "Image": "",
      "SellPrice": 1.0,
      "BuyPrice": 22000.0,
      "BuyCooldown": 1296000,
      "SellCooldown": 0,
      "KitName": null,
      "Command": [
        "oxide.grant user $player.id myminicopter.spawn",
        "oxide.grant user $player.id myminicopter.where",
        "oxide.grant user $player.id myminicopter.fetch"
      ],
      "SkinId": 0
    },
    "Teleportation_License": {
      "DisplayName": "Teleportation License",
      "Shortname": "teleportation.license",
      "EnableBuy": true,
      "EnableSell": false,
      "Image": "",
      "SellPrice": 1.0,
      "BuyPrice": 3000.0,
      "BuyCooldown": 1296000,
      "SellCooldown": 0,
      "KitName": null,
      "Command": [
        "oxide.grant user $player.id nteleportation.tpr",
        "oxide.grant user $player.id nteleportation.tpb",
        "oxide.grant user $player.id corpselocation.tp"
      ],
      "SkinId": 0
    },
    "Mini BackPack": {
      "DisplayName": "Mini BackPack",
      "Shortname": "minibackpack",
      "EnableBuy": true,
      "EnableSell": false,
      "Image": "",
      "SellPrice": 1.0,
      "BuyPrice": 3500.0,
      "BuyCooldown": 1296000,
      "SellCooldown": 0,
      "KitName": null,
      "Command": [
        "oxide.grant user $player.id backpacks.use.2"
      ],
      "SkinId": 0
    },
    "Medium BackPack": {
      "DisplayName": "Medium BackPack",
      "Shortname": "mediumbackpack",
      "EnableBuy": true,
      "EnableSell": false,
      "Image": "",
      "SellPrice": 1.0,
      "BuyPrice": 6500.0,
      "BuyCooldown": 1296000,
      "SellCooldown": 0,
      "KitName": null,
      "Command": [
        "oxide.grant user $player.id backpacks.use.4"
      ],
      "SkinId": 0
    },
    "Mega BackPack": {
      "DisplayName": "Mega BackPack",
      "Shortname": "megabackpack",
      "EnableBuy": true,
      "EnableSell": false,
      "Image": "",
      "SellPrice": 1.0,
      "BuyPrice": 10000.0,
      "BuyCooldown": 1296000,
      "SellCooldown": 0,
      "KitName": null,
      "Command": [
        "oxide.grant user $player.id backpacks.use.7"
      ],
      "SkinId": 0
    },
    "Paint My Sign": {
      "DisplayName": "Paint My Sign",
      "Shortname": "paintmysign",
      "EnableBuy": true,
      "EnableSell": false,
      "Image": "",
      "SellPrice": 1.0,
      "BuyPrice": 3000.0,
      "BuyCooldown": 1296000,
      "SellCooldown": 0,
      "KitName": null,
      "Command": [
        "oxide.grant user $player.id signartist.url"
      ],
      "SkinId": 0
    },
    "RemoverTool": {
      "DisplayName": "RemoverTool",
      "Shortname": "removertool",
      "EnableBuy": true,
      "EnableSell": false,
      "Image": "",
      "SellPrice": 1.0,
      "BuyPrice": 1000.0,
      "BuyCooldown": 1296000,
      "SellCooldown": 0,
      "KitName": null,
      "Command": [
        "oxide.grant user $player.id removertool.normal"
      ],
      "SkinId": 0
    },
    "Personal Patrol Heli": {
      "DisplayName": "Personal Patrol Heli",
      "Shortname": "personalpartrolheli",
      "EnableBuy": true,
      "EnableSell": false,
      "Image": "",
      "SellPrice": 1.0,
      "BuyPrice": 25000.0,
      "BuyCooldown": 1296000,
      "SellCooldown": 0,
      "KitName": null,
      "Command": [
        "oxide.grant user $player.id personalheli.use"
      ],
      "SkinId": 0
    },
    "Car License": {
      "DisplayName": "Car License",
      "Shortname": "car.license",
      "EnableBuy": true,
      "EnableSell": false,
      "Image": "",
      "SellPrice": 1.0,
      "BuyPrice": 5000.0,
      "BuyCooldown": 1296000,
      "SellCooldown": 0,
      "KitName": null,
      "Command": [
        "oxide.grant user $player.id garage.use"
      ],
      "SkinId": 0
    },
    "WorkBench Plus": {
      "DisplayName": "WorkBench Plus",
      "Shortname": "workbenchplus",
      "EnableBuy": true,
      "EnableSell": false,
      "Image": "",
      "SellPrice": 1.0,
      "BuyPrice": 2500.0,
      "BuyCooldown": 0,
      "SellCooldown": 0,
      "KitName": null,
      "Command": [
        "oxide.grant user $player.id buildingworkbench.use"
      ],
      "SkinId": 0
    },
    "TP Home": {
      "DisplayName": "TP Home",
      "Shortname": "tp.home",
      "EnableBuy": true,
      "EnableSell": false,
      "Image": "",
      "SellPrice": 1.0,
      "BuyPrice": 1500.0,
      "BuyCooldown": 0,
      "SellCooldown": 0,
      "KitName": null,
      "Command": [
        "oxide.grant user $player.id nteleportation.home"
      ],
      "SkinId": 0
    },
    "Box Manager": {
      "DisplayName": "Box Manager",
      "Shortname": "boxmanager",
      "EnableBuy": true,
      "EnableSell": false,
      "Image": "",
      "SellPrice": 1.0,
      "BuyPrice": 3000.0,
      "BuyCooldown": 1296000,
      "SellCooldown": 0,
      "KitName": null,
      "Command": [
        "oxide.grant user $player.id quicksort.use"
      ],
      "SkinId": 0
    },
    "Bgrade": {
      "DisplayName": "Bgrade",
      "Shortname": "bgrade",
      "EnableBuy": true,
      "EnableSell": false,
      "Image": "",
      "SellPrice": 1.0,
      "BuyPrice": 5000.0,
      "BuyCooldown": 1296000,
      "SellCooldown": 0,
      "KitName": null,
      "Command": [
        "oxide.grant user $player.id bgrade.all"
      ],
      "SkinId": 0
    },
    "SkinBox": {
      "DisplayName": "SkinBox",
      "Shortname": "skinbox",
      "EnableBuy": true,
      "EnableSell": false,
      "Image": "",
      "SellPrice": 1.0,
      "BuyPrice": 5000.0,
      "BuyCooldown": 1296000,
      "SellCooldown": 0,
      "KitName": null,
      "Command": [
        "oxide.grant user $player.id skinbox.use",
        "oxide.grant user $player.id skinbox.deployable",
        "oxide.grant user $player.id skinbox.playerwearable",
        "oxide.grant user $player.id  skinbox.deployable",
        "oxide.grant user $player.id  skinbox.weapon"
      ],
      "SkinId": 0
    },